Field
Various communication systems may benefit from appropriate bandwidth selection for interference measurements. For example, evolved universal mobile telecommunication system (UMTS) radio access network (E-UTRAN) systems may benefit from reference signal received quality (RSRQ) measurement configurations that take into account an identified need.
Description of the Related Art
When, for example, a 10 MHz long term evolution (LTE) cell is overlapping 5+5 MHz wideband code division multiple access (WCDMA) cells, such as two single carrier WCDMA cells or a dual carrier high speed packet access (HSPA), and reference signal received quality (RSRQ) measurements are carried out over the central seventy-two subcarriers, six resource blocks (RBs), this particular measurement would be carried out in a guard band between the two WCDMA cells. Consequently, the RSRQ would be overestimated, and because RSRQ is used for handover decisions, the mobility functionality of the system may also be affected.
Various approaches may be provided for addressing this situation. For example, complex approaches including new signaling elements may be used to try to require the UE, under certain given conditions, to perform RSRQ measurements over a wider bandwidth as compared to current minimum requirement of six physical resource blocks (6PRBs).
Current specifications only require a user equipment to perform measurements over the six center PRBs, seventy-two subcarriers, in E-UTRAN for both intra-frequency (intra-F) measurements and inter-frequency (inter-F) measurements.
Third generation partnership project (3GPP) technical specification (TS) 36.331, which is hereby incorporated herein by reference in its entirety, includes an option for the network to indicate the bandwidth of configured carriers using the ‘allowedMeasBandwidth’ parameter. This option is used to be able to restrict the ‘maximum’ measurement bandwidth (BW) potentially used by the UE in case the UE chooses to perform measurements on wider bandwidth than required. Thus, the parameter indicates maximum bandwidth that can be used on the indicated carrier frequency and UE is not allowed to use wider measurement BW than indicated by ‘allowedMeasBandwidth’ parameter.
Thus, in general, the UE may choose to perform measurements of detected cells using wider bandwidth than the minimum requirement of six PRBs, but is not required to do so. Additionally, the bandwidth used is conventionally not allowed to exceed the indicated ‘AllowedMeasBandwidth’.